4.2 a Flashcards
ore
rock that contains metals that can be extracted
what is steel
alloy of iron and carbon, as well as some other elements
list stages of steel extraction
raw material preparation
ironmaking
steelmaking
continuous casting
semi finished products
rolling
steel construction products
environmental implications of extracting metal from ores
need to replace natural resources
energy consumption
economic implications of extracting metal from ores
gov spending
effect on business climate
stable economic growth
social implications of extracting metal from ores
developing goods that can enhance human well being
empowering local communities
what affects metal durability
its grain size
large grains are formed through…
slow cooling
small grains are formed through…
fast cooling
large grains have increased…
tensile strength
toughness
ductility
alloys
combining at least one metal w other materials to produce another that is more useful for a specific task
list common alloys
brass
bronze
steel
copper
what does alloying generally do in comparison to pure metals
increases strength and hardness while decreasing ductility
superalloys
alloy that exhibits excellent mechanical strength, resistance to creep deformation, oxidation resistance
creep in relation to metals
tendency of a metal to slowly deform due to long term exposure to stress
work hardening
toughening metal through plastic deformation
tempering
heating process that generally follows work hardening; increases toughness of metal
annealing
metal is heated and allowed to cool slowly to be made easier to work with – increases ductility
ferrous metals
contain iron
which metals are magnetic
ferrous
potential issues w recovery and disposal of metals
not all alloys are identifiable
some have lower melting points => can vaporise during recycling process and cause pollution
